Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Cleanup of userland __P use

Commit IPv6 support for FAST_IPSEC to the tree.
This commit includes all remaining changes for the time being including
user space updates.

Submitted by: bz
Approved by: re

- do hexdump on send. set length field properly
- check for encryption/authentication key together with algorithm.
- warned if a deprecated encryption algorithm (that includes "simple")
is specified.
- changed the syntax how to define a policy of a ICMPv6 type and/or a
code, like spdadd ::/0 ::/0 icmp6 134,0 -P out none;
- random cleanup in parser.
- use yyfatal, or return -1 after yyerror.
- deal with strdup() failure.
- permit scope notation in policy string (-P
esp/tunnel/foo%scope-bar%scope/use)
- simplify /prefix and [port].
- g/c some unused symbols.

Obtained from: KAME

- style
- rename variable
- use strlcpy
- const'fy

Obtained from: KAME

Use NI_xxx macros.

Obtained from: KAME
MFC after: 1 week

Sync with recent KAME.
This work was based on kame-20010528-freebsd43-snap.tgz and some
critical problem after the snap was out were fixed.
There are many many changes since last KAME merge.

TODO:
- The definitions of SADB_* in sys/net/pfkeyv2.h are still different
from RFC2407/IANA assignment because of binary compatibility
issue. It should be fixed under 5-CURRENT.
- ip6po_m member of struct ip6_pktopts is no longer used. But, it
is still there because of binary compatibility issue. It should
be removed under 5-CURRENT.

Reviewed by: itojun
Obtained from: KAME
MFC after: 3 weeks

synchronize with latest kame tree.

behavior change: policy syntax was changed. you may need to update your
setkey(8) configuration files.

libipsec and IPsec related apps. (and some KAME related man pages)

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project